This invention relates to an apparatus for receiving a plurality of pyrotechnic devices and for igniting such devices in a given sequence.
Of interest is application Ser. No. 383,650 filed Jul. 24, 1989 entitled Electrically Activated Detonator with Pyrotechnic Device Receiving Terminals and Method of Making in the name of Joseph L. La Mura et al. and assigned to the assignee of the present invention now U.S. Pat. No. 4,951,570.
Pyrotechnic devices are useful in many different applications. In one particular application, the military employs pyrotechnic devices for training of troops to simulate the receipt of a xe2x80x9chitxe2x80x9d at a target. Training in the military is focused on offense and defense. In both instances there is a need for an apparatus that can simulate the firing of large caliber rounds, e.g. 105 mm, mounted on armor vehicles. The following are examples of training exercise modes. In one mode, armor vehicles are pitted against armor vehicles both vehicles moving, utilizing laser beam technology. Hit detectors are placed on the opposed vehicles. A gunner fires a large caliber weapon at the opposing vehicle emitting a laser beam which does not have any audio-visual effects. A pyrotechnic ignition apparatus (PIA) is mounted on the armor vehicle turret and is electrically connected to the gunner""s trigger mechanism. Upon firing the simulated large caliber round, the gunner activates his laser to fire a beam of light and at the same time his action ignites a round (a pyrotechnic device), which provides the audio-visual effects of firing a large caliber round. Both the offense and defense troops can visually observe when they have been fired upon.
In a second mode, armor tank pitted against armor tank, the offense moves onto stationary defense. During this mode, the offense is moving through a prescribed tank course where simulated tank targets are activated and come into the view of the offense. At the same time that the tank target is activated, a device is ignited which simulates the defense (tank) fire power audio-visual effects as viewed by the offense. Throughout the offensive course, all hits scored on the defensive tank targets are registered on a computer network. A PIA device is ignited with each hit, setting off sound, smoke and flash at the defensive tank target site. The PIA has an interconnecting cable from the tank target. The tank target registers hits from the opposing forces via a tuned crystal which is attached to the tank target. When the tank target is hit by a fired tank round the resonate frequency of the crystal is activated transmitting an electrical pulse to the PIA via the interconnecting cable which in turn activates the PIA to ignite an audio-visual pyrotechnic device for the offense indicating that he has destroyed the defense tank.
In a third mode, armor tank versus armor tank, the offense is moving, the defense is stationary. The offense are tank target mechanisms which are placed at 100 meter intervals extending to 5 k meters on a specific tank range. Tank targets are activated by remote control starting at 5 k meters from the stationary defense. Each time a tank target is activated, a pyrotechnic device is ignited to simulate the tank gunfire of the simulated approaching tanks.
When the offensive simulated tanks come into the range of fire of the defensive tanks, the defense then fires their weapons at any selected ones of the targets that come into their sights. The defensive force fire live ammunition at the tank targets and the tank targets have the capacity of scoring each received xe2x80x9chitxe2x80x9d round via a crystal detector. This information is transmitted via a computer network. At the time that the tank target receives a xe2x80x9chitxe2x80x9d, a pulse is generated that automatically ignites a PIA device which provides an audio-visual (flash and smoke) indication that the target has been hit. The pulse is transmitted via an interconnecting cable as a radio signal. These systems need a PIA which can ignite devices in large numbers repetitively and reliably.
The pyrotechnic ignition apparatus (PIA) in one implementation designed by the assignee of the present invention and demonstrated to the U.S. government in a prototype may be an array of firecracker type devices comprising pyrotechnic material filled in an insert which fits in an array of six inch tubes mounted on a support. Each round of the pyrotechnic device is exploded in turn in a sequence.
An electrically activated match is in the material of each insert and has a pair of protruding wires which are manually connected to the firing circuit. The manual connection occasionally causes the devices to be connected in an incorrect sequence. Electrical power to explode the pyrotechnic devices is received remotely via a cable. Each of the pyrotechnic devices is ignited via a digital circuit. The system has memory via a digital counter for continuing the sequence if the sequence is temporarily interrupted. Also, the sequence can be restarted from the beginning by resetting the counters with a reset switch using an R-C network. This system has the problem in that in certain conditions, the system can not reset. The sequence used insures that each device is fired once and that the next received firing pulse fires the next unfired device in the sequence. The misfiring of the devices out of sequence due to miswiring is a serious drawback.
In addition, the circuit includes a detector which indicates a valid received device in the array is in condition for ignition. The detector tests whether or not a pyrotechnic device is ready and in condition for ignition. In these kinds of systems for military purposes it is typical to use a lock-out system for preventing the system from firing immediately after loading in the interest of safety since loading is done manually. The above simulation apparatus, however, is somewhat awkward to use because of the need for manual reconnection of each of the devices during reload.
Other pyrotechnic systems are known for generally firing pyrotechnic devices at target areas in response to fire command signals received by the target. Generally, these various systems suffer from the disadvantage of requiring cumbersome and awkward reloading of the pyrotechnic device arrays or the devices are too small to be observed at large distances. Generally, some of these systems employ mechanical detonating devices which tend to deteriorate or misoperate due to contamination, corrosion and temperature variations. For example, sand and dirt clog mechanical impact detonators. Other systems are relatively awkward to use and not generally realistic. See for example, U.S. Pat. No. 4,245,403 wherein each detonater is wired to a circuit panel and a separate gas system generates the noise.
The present inventors desire to provide a remotely operated pyrotechnic devices which can simulate a hit or firing of rounds from different kinds of weapons. Because of the distance at which the target is placed from the firing weapon in different training modes, it would normally be difficult or impossible for the firing weapon operator to visibly observe the presence of personnel in some of the target areas. Therefore, it is incumbent to insure for safety purposes that the target area pyrotechnic devices cannot be set off upon receipt of an ignition command signal while personnel are in the target area, e.g. loading devices in the PIA.
The present inventors recognize a need for a pyrotechnic ignition apparatus for use with a radio operated system which has long life, is capable of operating safely with personnel nearby in the presence of premature emitted firing signals and for utilizing a minimum amount of electrical power for remote battery operation. The present inventors also recognize a need for a pyrotechnic apparatus which is capable of quick and simple reload while permitting such reloads to take place with relative safety. A problem with prior pyrotechnic apparatus is that, normally, when they include a plurality of pyrotechnic devices, not all such devices may be fired in a given time period. An array of pyrotechnic devices in a apparatus may include, for example, 20 pyrotechnic devices, only 10 of which are fired in a given period. In the next period, after the system has been set off, it may be desired to reload the 10 fired devices or continue firing the remaining 10 unfired devices or fire a selected portion of the remaining 10 unfired devices. Present systems however do not have the capability of handling such variables. In addition, the present inventors recognize a need for a pyrotechnic apparatus which can simulate the firing of different size rounds, for example 20 millimeter, 40 millimeter, and so on with one pyrotechnic apparatus.
A pyrotechnic apparatus in accordance with one embodiment of the present invention comprises magazine means for releaseably receiving a plurality of pyrotechnic devices. Device ignition means are included which include means for releaseably receiving the magazine. The ignition means include contact means for ohmically contacting each of the received pyrotechnic devices and for selectively electronically igniting the received pyrotechnic devices.
In accordance with one feature of the apparatus of the present invention the means for selectively igniting includes control means for igniting at least a portion of the pyrotechnic devices in a given ignition sequence. Other features include control means including means for selectively igniting a first portion of the received plurality of devices in a given sequence in a first ignition cycle and for selectively igniting a second portion of the received plurality of devices in a second ignition cycle. Still other means are included wherein programming means selectively commence an ignition cycle at the beginning of that cycle next following the last ignition cycle in a sequence in selected different ignition cycles or at the beginning of the sequence.